Recently confirmed the made in China valve stems I bought on EBay for $4/pr are the identical product sold in motorcycle stores for ~$25 under the BikeMaster brand name. There are also similar valve stems to these with a B stamped on them. The ones with a B are Italian made and sold under a few different Italian brand names. Those without a B are made in China. All are basically the same product with similar quality. They are handy to easily get an air hose, particularly the screw on kind, on the front wheel when the brake rotors would otherwise obstruct access. Note they need to be mounted, pointing out to right, for access when the bike is on side stand. They come in 2 sizes, you need the 11.3mm rim hole size for Kawasaki. Good value for money, and a worthwhile addition IMO when mounting new tires.